The present invention relates generally to the field of seat belt buckles. More specifically, the present invention relates to the field of buckle scabbards for seat belt buckle systems in which the scabbard is configured to prevent disengagement of a latch plate to a buckle head.
Conventional seat belt buckle systems generally include a seat belt with a latch plate, and a pretensioner that is connected to a seat belt buckle. The buckle assembly includes a buckle head, a stalk that connects the buckle head to either a vehicle component or a pretensioner, and a scabbard that covers part of the stalk and buckle. In conventional seat belt buckle systems, when the system undergoes shock loading, the latch plate may be disengaged, thereby allowing an occupant's seat belt buckle to become unlatched. The shock loading can be caused by hard contact between a pretensioner accelerated buckle head and vehicle components. The shock loading can be caused by firing of the pretensioner, which imparts a sudden acceleration to the buckle head that is partially resisted by the scabbard. Shock loading can also be caused by contact between a buckle head in motion, when the pretensioner fires and reels in the stalk and forces the buckle head to move towards the pretensioner, and a hard portion of a vehicle seat. The shock load may also be caused by a sudden deceleration of the buckle head at the end of the pretensioner's stroke. Further, in conventional seat belt buckle systems, the scabbard is crushed axially as the stalk shortens, such as during a shock loading, which prevents the scabbard from offering any protection of the buckle head.